Now, the Chicago Cubs are headed into the All-Star break in a fashion as uninspiring as the start of their season.

In the top of the first inning against the Pittsburgh Pirates — the Cubs’ final game of the first half — left-hander Jon Lester allowed 10 runs on six hits and walked three. While just four of those runs were earned, the Pirates roughed up the Chicago ace regardless, handing him the worst start of his 13-year career.

The debacle marked the first time in Lester’s career that he failed to escape the first inning, and was also the first time the Cubs allowed 10-plus runs in the first inning since 1998.

"It kind of speaks for itself," Lester said. "It's embarrassing."

It was Pittsburgh's highest-scoring inning since it got 10 in the seventh against Colorado on May 17, 2009. It was the first time it scored 10 in the first inning since June 8, 1989, against Philadelphia.

Lester’s struggles from the get-go were the pinnacle of a first-half in which the Cubs have struggled on the defensive end to open games. As it stands, Chicago leads the majors in first-inning runs allowed — conceding 80 runs in the first frame through 88 games.

The 10-run onslaught began with a single from Pirates second baseman Josh Harrison, before he advanced to second on catcher Francisco Cervelli’s ground out.

Andrew McCutchen proceeded to draw a walk before third baseman Kris Bryant committed an error to load the bases. Three consecutive hits by Josh Bell, Jose Osuna and Jordy Mercer then gave the Pirates a 5-0 lead.

From there, things simply went from bad to worse. Lester walked two to load the bases before Cervelli hit a grand slam, and McCutchen followed it up with a solo shot of his own.

Just like that, the Pirates had buried the Cubs in a 10-0 hole before tacking on another in the fourth and losing 14-3.

"Throw up 10 like that in the first inning, it was huge," McCutchen said. "We kept going, we kept pushing and didn't stop there in the first."

The Cubs dropped to 43-45, which would put them 5.5 games out of first in the NL Central.